#include <iostream>
#include <vector>
using namespace std;

class Solution {
public:
    int takeAttendance(vector<int>& records) {
        int left = 0, right = records.size() - 1;
        while (left < right)
        {
            int mid = left + (right - left) / 2;
            if (mid == records[mid]) left = mid + 1;
            else right = mid;
        }
        if (records[left] == left) return left + 1;
        return left;
    }
};

int main()
{

	return 0;
}